NAME
SDL_SetEventFilter - Sets up a filter to process all events before they
are posted to the event queue.
SYNOPSIS
#include "SDL.h"
void SDL_SetEventFilter(SDL_EventFilter filter);
DESCRIPTION
This function sets up a filter to process all events before they are
posted to the event queue. This is a very powerful and flexible
feature. The filter is prototyped as:
typedef int (*SDL_EventFilter)(const SDL_Event *event);
If the filter returns 1, then the event will be added to the internal
queue. If it returns 0, then the event will be dropped from the queue.
This allows selective filtering of dynamically.
There is one caveat when dealing with the SDL_QUITEVENT event type. The
event filter is only called when the window manager desires to close
the application window. If the event filter returns 1, then the window
will be closed, otherwise the window will remain open if possible. If
the quit event is generated by an interrupt signal, it will bypass the
internal queue and be delivered to the application at the next event
poll.
Note:
Events pushed onto the queue with SDL_PushEvent or
SDL_PeepEvents do not get passed through the event filter.
Note:
Be Careful! The event filter function may run in a different
thread so be careful what you do within it.
SEE ALSO
SDL_Event, SDL_GetEventFilter, SDL_PushEvent